The present invention relates to a rear vehicle body structure for pickup trucks, in particular, to the rear vehicle body structure for pickup trucks having a structure for the back panel which separates the passenger compartment and cargo bed and includes an opening with a hinged opening and closing panel.
The present application claims priority from Japanese Patent Application No. 2001-400215, the disclosure of which is incorporated herein by reference for all purposes.
In response to the diversifying needs of consumers, car manufacturers have produced more and more car-based pickup trucks and car- or truck-based sport utility vehicles (SUVs) in recent years, as these vehicles offer both the practicality of trucks with a high cargo capacity and the comfortability of passenger cars. Some of these pickup trucks are provided with an opening with the hinged opening and closing panel in the lower part of their back panel which separates the passenger compartment from a cargo bed. Whenever it is necessary, the rear seats are folded down, and the opening and closing panel is pushed either forward or backward to open the opening, so that more space can be used for loading cargo.
The pickup trucks have a monocoque vehicle body similar to that of cars unlike recreational vehicles (RVs) which have a frame structure. Therefore, if the back panel separating the passenger compartment and the cargo bed has an opening in its lower part, the lower end of the back panel will have a decreased rigidity. If the lower end of the back panel is not sufficiently rigid, the bottom edge of the opening in the back panel cannot stand heavy cargo load and may deform. Since the bottom edge of the opening is often used for holding a mounting end of a cargo tray which is placed over the cargo bed floor, it needs to have sufficient strength to support the cargo load.
Another problem is that the back panel with an opening therein requires a structure which prevents rain water from entering inside the truck. Normally, a weather strip is fitted to an entire circumferential edge of the opening, so that, when the opening and closing panel is closed, the weather strip fits in tightly between the opening and closing panel and the back panel by elastic deformation and seals a gap thereof, preventing rain water from entering the passenger compartment and insulating noise. However, if the opening and closing panel is opened during it is raining, water runs into the passenger compartment through the opening. If the opening and closing panel is designed to be pushed down forward, i.e., toward the passenger compartment, water gathered in the weather strip may also flow into the compartment when the opening and closing panel is opened.
The present invention has been devised to resolve the problems encountered by the conventional rear vehicle body structure for pickup trucks. An object of the present invention is to provide a rear vehicle body structure for pickup trucks, with which rigidity of the lower end of the back panel, in particular, the bottom edge of the opening where a cargo tray is mounted, is increased so as to prevent deformation of the lower end of the back panel due to heavy cargo load, and with which rain water entering into the passenger compartment is swiftly drained to the outside of the pickup trucks.
To achieve the above object, the rear vehicle body structure of the pickup truck has the passenger compartment, a cargo bed, and a back panel separating the passenger compartment and the cargo bed, the back panel including an opening formed therein which is opened and closed by an opening and closing panel. According to the first aspect of the present invention, the rear vehicle body structure includes a lower back panel constituting a lower end of the back panel and defining a bottom edge of the opening in the back panel, a forward flange extending a predetermined distance from a front end portion of the lower back panel, a front circumferential edge portion of the forward flange being bent upward, a backward flange extending a predetermined distance from a rear end portion of the lower back panel, and a rear floor panel connected to the forward flange and the backward flange of the lower back panel, whereby the lower back panel and the rear floor panel form a closed space together.
According to the second aspect of the invention, the rear vehicle body structure according to the first aspect may further include a drain part formed at a predetermined position in the forward flange so as to extend through the rear floor panel.
According to the third aspect of the invention, the rear vehicle body structure according to the first or second aspect may further include a cross member extending in a widthwise direction of the pickup truck on a lower face of the rear floor panel where the lower back panel is connected to an opposite face thereof, such that the cross member and the rear floor panel form a closed space together.
According to the fourth aspect of the invention, in the rear vehicle body structure according to any of the first to third aspects the lower back panel may be made up of a front lower back panel and a rear lower back panel separated in front to rear direction of the pickup truck, where the front lower back panel may be further separated into an upper part and a lower part. One of the above mentioned structures may be formed with a beaded surface so that the upper part and the lower part are connected together via the beaded surface.
According to the fifth aspect of the present invention, in the rear vehicle body structure according to the fourth aspect, a side end portion of the lower part of the front lower back panel may be connected to the rear lower back panel, whereby the closed space defined by the lower back panel and the rear floor panel is divided into an upper section and a lower section.
According to the sixth aspect of the invention, in the rear vehicle body structure according to any of the first to fifth aspects, the rear floor panel may be beaded along front to rear direction of the pickup truck at a portion where the forward flange of the lower back panel is connected thereto.
According to the seventh aspect of the invention, in the rear vehicle body structure according to any of the first and the third to sixth aspects, a part of the front circumferential edge portion of the forward flange may be bent downward, and a drain part may be formed in the rear floor panel below the bent portion of the forward flange so as to extend through the rear floor panel.
According to the eighth aspect of the invention, in the rear vehicle body structure according to any of the second to seventh aspects, the drain part may further include a one-way plug fitted therein.